Polymers of 3-methylenephthalide and process of preparation



Patented Dec. 22, 1953 POLYMERS OF 3-METHYLENEPHTHALIDE AND PROCESS OF PREPARATION Harry W. Coover, J r., Joseph B. Dickey, and Newton H. Shearer, Kingsport, Tenn, assignors to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey No Drawing. Application September 20, 1952, Serial No. 310,736

6 Claims.

This invention relates to polymers'of 3-methylenephthalide and to a process for preparing them.

This application is a continuation-in-part of our application Serial No. 78,222, filed February 24, 1949, now U. S. Patent 2,618,627, issued November 18, 1952.

3-methylenephthalide has the following formula:

o -JJ=CHI and can be prepared by methods described by Gabriel, Berichte, vol. 17, page 2521 (1884), or Yale, Jour. Am. Chem. Soc, vol. 69, page 1547 (1947). This compound can also be named 3 methylene-l (3H) -is0benzofuranone.

Gabriel noted that a residue, which apparently was the result of slight polymerization, was obtained by his method of preparation. While Gabriel was only able to obtain a polymer of very low molecular weight, we have found that polymers of high molecular weight can be obfibers, sheets, etc.

It is, accordingly, an object of our invention to provide an improved method for preparing polymers of 3-methylenephthalide of a high molecular weight. It is a further object of our invention to provide interpolymers of 3-methylenephthalide and a method for preparing them. A further object is to provide films, fibers, sheets, etc. prepared from our new, high molecular weight polymers and means for obtaining such materials. Other objects will become apparent from a consideration of the following description and examples.

According to our invention, we prepare polymers of 3-methylenephthalide of high molecular weight by subjecting 3-methylenephthalide or a mixture of 3-methylenephthalide and of from 1 to 3 other polymerizable compounds to the influence of a peroxide polymerization catalyst.

Typical peroxide polymerization catalysts include carboxylic acid peroxides, e. g. acetyl, 'propionyl, benzoyl, acetyl benzoyl, etc. peroxides,

the alkali metal persulfates, e. g. sodium, potassium, etc. persulfates, ammonium persulfate, hydrogen peroxide, t-butyl peroxide, the alkali metal perborates, e. g. sodium perborate, etc.,etc. The amount of catalysts employed varies and generally is a function of the compounds being polymerized. Usually from 0.01 to 3.0 percent by weight, based on the total weight of the materials being polymerized, is sufficient, although larger amounts can be used when so desired.

The polymerization can be accelerated by heating, the reaction mixture, if desired. For example, temperatures varying from room temperature (about C.) to the reflux temperature of the reactants (usually about 100 C.) can be advantageously employed. Temperatures varying from to C. have been found to be especially use 111 in. utilizing our invention.

The process of our invention can be carried out en masse, or the materials to be polymerized can be dissolved in a suitable solvent and the solution subjected to polymerizing conditions in the presence of at least one of the catalysts set forth above. When volatile or low boiling solvents are employed, the polymerization can be carried out under superatmospheric pressures. Typical solvents or diluents include benzene, toluene, xylenes, lA dioxane, n-hexane, acetonitrile, glycolonitrile, etc. A solvent is advantageously selected which is also a solvent for the interpolymer, although solvents which dissolve the monomers being polymerized, but not the interpolymer formed, can be employed. The polymers can be obtained from the solutions by pouring the solution into a liquid in which the polymers are insoluble, e. g. water, methanol, acetic acid, etc., or the solvent can be evaporated oil from the solution.

S-methylenephthalide can also be polymerized according to our invention by a bead or emulsion method in which water or some other medium .in which 3-methylenephthalide alone (or mixtures of 3-methylenephthalide and from 1 to 3 other p-olymerizable compounds) is insoluble, is employed as a dispersing medium, with or without emulsifying agents (e. g. soap, starch,

polyvinyl alcohol, gum arabic, etc.). Bead or emulsion methods, as well as solution methods, offer the advantage that a more uniform polymerization can be effected, and these methods largely or entirely avoid any external heating. After polymerization hasbeen efiected, the emulsions can be broken by the addition of methanol; acetic acid, etc. f

The homopolymers of 3-methylenephthalide obtained according to our invention have a Small amounts (e. g. 1-5O%v by1weight,: ;based'. on the homopolymer) of N,N-dimethylformamideare useful in plasticizing poly-3-rnethylenephthalide, while larger amounts: (e: g; thosegiving a solution containing 15-20% by weight of solids) give useful solutions as outlined-i above. N,N-dimethylacetamide-is also a useful solvent for: our new. homopolymers, and: can. be. usem in armanner. similar,- to the N,N- dimethylformamide.

In.- the preparation of interpolymers, from 3- methylenephthalide generally; any ratio ofthe 3: methylenephthalide to the total polymerizable compoundspresent can be: used. We. have found that polymers". of: particular: utility can be.- ob.- tained by subjeeting a reaction mixture contain? ing.;from 5 toQ-bepercent of;.3-methy1enephthalide by weight ,.based;on .thetotal weight. of polymer,- izable 1 compounds present, to the. actionof: one of' thecatalysts setforth above. The remaining; 5 to 95 percent. by: weight of polymerizable compounds-is advantageously composed of from 1: c013; polymerizableacompounds; other. than 3- methylenephthalide. Such compounds. include polymerizable. organicv compounds containing; a non-aromatic or acyclic C=C group. Compounds; wherein: at-lleast two. of the valencies of the carbon atoms inthe above group are satisfied b hydrogenatoms; e; g. compounds containing a- CH2=C and: a. CH2.==GH group have been found: to beespecially: useful in our invention. Compounds useful in preparing interpolymers according to cur -invention include, for example, acrylates: a-methacrylates, fumarates, maleates, malei'c. anhydride; acrylonitrile, a-substituted acrylonit'ri'le; acrylamides; vinyl sulfones, vinyl sulfonami'des; alkenyl. ketones; vinyl halides, vinylidene: halides, .polyha'logenoethylenes (e. g. tetrafluoroethyiene) hydrocarbonscontaining olefinic imsaturation, etcz.

Th'e=.acrylates or' c-methacrylates we can ade vantaigeously use: in: our invention.- can be; represented by the: following general formula:

wherein R represents a member selectedfromthe group. consisting of a hydrogen atom, a methyl group and; an acyloxy group,.such as acetoxy. propionoxy. n-butyroxy, isobutyroxy,.etc. groups (e. g an acyl" group of, an. aliphatic carboxylic acii'having 2 to 4 carbon atoms), and R1 represents amember selected from the group consisting. of'ahydrogen atom,.an alkyl group,such as methyl} ethyl, n-propyl, isopropyl, n-butyl, isobut'yl, secondary ancltertiary butyl, etc. groups (e. g. an alkylgroup. representedby the formula ChHmm wherein-.1 represents. a. positive integer of from L to 4) anaralkyligroup, such asbenzyl, ,e-phenyl'ethyl; etc. groups, or an alkenylgroup, suchas vinyl,,allyl, fi-methallyl, crot'yl, isopropenyhetc. groups, (e. g. an alkenylgroup repres sented by the formula CnH2n-1 wherein n represents a positive integer from 2 to 4). Typical are methyl acrylate, methyl a-methacrylate, ethyl acrylate, ethyl a-methacrylate, n-propyl acrylate, mpropyl. aemethacrylate; isopropyl acrylate, isopropyl wmethacrylate, rr-butyl acrylate, n-butyl a-methacrylate, isobutyl acrylate, isobutyl amethacrylate, benzyl acrylate, benzyl a-methacrylate, vinyl acrylate, vinyl a-methacrylate, al-

ylyl acrylate; allyl a-methacrylate, 2-methallyl acrylate, Z-methallyl a-methacrylate, methyl aacetoxyac-rylate, ethyl,- a-acetoxyacrylate, n-butyl e-butyrmrya'cr ylate; etc.

The.olefinic::nitriles with which 3-methylenei phthalide can. be interpolymerized can advantageously be represented by the following general formula:

CH2=C-CEN wherein Rarepresentsla member. selected; from the group. consisting, of, a. hydrogen: atom,-, a methyl" group, or. an. acyloxy group, such as acetoxy, propionox-y, n-butyrox, isobutyroxy, etc. groups, (e. g.- an acyl group of, an aliphatic car-'- boxylic acid having 2 to 4 carbon atoms). il-R v cal. are, acrylonitrile,cemethacrylonitrile; e-acetoxyacrylonitrile, a-n-butyroxyacrylonitrile, etc;v

The olefinic ketones which we can advantageously use in our invention can be represented by the following general formula:

wherein R3 represents amember selected from the group consisting of analkylgroup, suchlas methyl, ethyLn-propyl, isopropyl, n-butyl isobutyl, etc. groups (e. g. analkyl-groupof thezfore mula CHI-Iran wherein. n representsa. positive integer fronrl, to 4.) and, analkenyl groumsuch as vinyl, ii-methallyl, isopropenyl, crotyl, etc. groups (e. g. analkenyl group-of: the formula CnH2n-1 wherein. n. represents a; positive integer from 21104), and R4 representsanalkenyl group,-

, such as; vinyl, allyl, cemethallyl; isopropenyl,

crotyl, etc. groupsv (e. g. an alkenyl group of the formula CnHZn-LWhEIBiIl nrepresentsa positive integer. from- 2- to. 4 Typical are methyl isopropenyl ketone; methyl vinyl ketone, n.-butyl vinyl ketone, ethyl isopropenyl ketone, divinyl ketone, diisopropenyl ketone, diallyl ketone, etc;

The olefinic acrylamides which we can ad'- vantageously use can be represented'by the'following general formula:

wherein R5 represents a member selected from the group, consisting of a hydrogen, atom, a methyl group and an acyloxy group, such as acetoxy, propionoxy; n-butyroxy, isobutyroxy, etc; groups (e. g. an acyl group of a carboxylic acid having Z-to 4 carbon atoms). Typical are acrylamida, a-methacrylamide, a-acetoxyacrylamide, etc.

The maleates or fumarates which we. can expeditiously use. can bev represented by the following general" formula:

0 mo-h-crmcuJB-nm wherein. R5. andR'z eachrepresents a member, se lected from, the. group, consisting of, a hydrogen 6130111,, an alkyl group, such as methyl, ethyl.

n-propyl, isopropyl, n-butyl, isobutyl, etc. groups (e. g. an alkyl group having the formula CnH2n+l wherein n is a positive integer from 1 to 4), an aralkyl group, such as benzyl, ,c-phenylethyl, etc. groups, and an alkenyl group, such as vinyl, allyl, p-methallyl, crotyl, etc. groups (e. g. an alkenyl group of the formula CnH2n-1 wherein n represents a positive integer from 2 to 4). Typical are maleic acid, monomethyl maleate, monomethyl fumarate, dimethyl maleate, dimethylfumarate, diethyl maleate, diethyl fumarate, di-n-propyl maleate, di-n-fumarate, diisopropyl maleate, diisopropyl fumarate, di-n-butyl maleate, di-nbutyl fumarate, diisobutyl maleate, diisobutyl fumarate, dibenzyl maleate, dibenzyl furnarate, diallyl maleate, etc.

The olefinic carboxylic acid esters which we can advantageously use can be represented by the following general formula:

wherein Ra represents a member selected from the group consisting of a hydrogen atom, an alkyl group, such as methyl, ethyl, n-propyl, isopropyl, etc. groups (e. g. an alkyl group of the formula C11H2n+1 wherein n represents a positive integer from 1 to 3), an aryl group, such as phenyl, o-, mand p-methylphenyl, etc. groups (e. g. a mononuclear aryl group of the benzene series having 6 to 10 carbon atoms), and a substituted aryl group, such as chlorophenyl, carbovinyloxyphenyl, i. e.

o0o11=orn etc. groups. Typical are vinyl formate, vinyl acetate, vinyl propionate, vinyl n-butyrate, vinyl isobutyrate, vinyl benzoate, vinyl chlorobenzoate, divinyl phthalate, etc.

The olefinic hydrocarbons with which we can interpolymerize 3-methylenephthalide can be represented by the following general formula:

wherein R10 and R11 each represents a member selected from the group'consisting of a hydrogen atom and an alkyl group, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, etc. groups (e. g. an alkyl group of the formula CtH2n+1 wherein n represents a positive integer from 1 to 4), and

R12 represents a member selected from the group consisting of a hydrogen atom, a methyl group and an ethyl group. Typical are vinylsulfon amide, N-methyl vinylsulfonamide, N-n-butyl isopropenylsulfonamide, etc.

Thevinyl halides which we can advantageously i to a clear, hard mass.

use can berepresented by the following general formula: v

CHpO-Rm wherein R13 represents a halogen atom, such as chlorine, bromine, iodine, or fluorine and R14 represents a member selected from the group consisting of a hydrogen atom, a methyl group and a halogen atom, such as chlorine, bromine, iodine, or fluorine. Typical are vinyl chloride, vinyl bromide, vinyl fluoride, isopropenyl chloride, vinylidene chloride, vinylidene bromide, vinylidene fluoride, etc.

Other polymerizable compounds not embraced by the above formulas which can advantageously be utilized in our invention include maleic anhydride, itaconic anhydride, N-vinylphthalimide, N-vinylmaleimide, vinylpyridine, chlorotrifluoroethylene, l,l-dichloro 2,2 difluoroethylene, tetrafluoroethylene, 2 methoxybutadiene 1,3, etc.

Certain so-called activating agents can be used in conjunction with the peroxide polymerization catalysts, if desired. Such agents include, for example, sodium bisulfite ferrous sulfate, etc. Chain length regulators, e. g. dodecyl mercaptan, etc. can also be used, if desired.

The following examples will serve to illustrate further the manner whereby we practice our invention.

Example 1.PoZy-3-methylenephthaZide- Solution method 10 g. of 3-methylenephthalide were dissolved in cc. of acetonitrile and 0.01 g. of acetyl peroxide was added. Thesolution was then heated on a water bath for 28 hours at 40 C. The resulting white polymer was obtained as a swollen mass, which was found to be soluble in a 50/50 mixture of acetonitrile and dimethylformamide. The dried polymer had a melting point of 320 C.

t-Butyl peroxide also was satisfactory for the polymerization, although slightly higher temperatures, e. g. 60-80 C. had to be used.

Example 2.-Interpolymer of styrene and B-methylenephthalide 9 g. of styrene, 1 g. of 3-methylenephthalide, and 0.02 g. of benzoyl peroxide were placed in a flask, and the air in the flask was replaced with gaseous nitrogen. The flask was then heated on a water bath at 60 C. until its contents had set The polymer dissolved in chlorobenzene and had a softening point of C. It was found to be readily adaptable for molding purposes.

A molecularly equivalent amount of 2,5-dichlorostyrene can be used in place of the styrene in the above example. The resulting product is obtained in the form of a clear, hard mass.

Example 3.--PoZy-3--nethylenephthalide Bulk method soluble in N,N-dimethylacet=amide.

Example 4.Interpolymer of acrylonitrzle and 3-methylenephthalide 5 g. of acrylonitrile, 5 g. of 3-methylene- 'phthalide, and 0.01 g. of acetyl peroxide were '2 heated o ether. in; aislasszhcttle for 1 2 hours; at 60 C. The white, powdery polymer had; a; sci;- tening point of 180 C. and was soluble in di methylformamide.

The softening point of interpolymers of acrylonitlfile andyZi-methylenephthalide can; bewariedby regulatingthe ratio of acrylonitrile to; 3-- methylenephthalide. Generally the higher the percentage of 3-methylenephtha1ida the.- higher the melting point of the interpolymer.

Example 5.Poly-3 methylenephthalide Emulsion method g. of 3-methylenephthalide were suspendcd: in cc. of distilled water to which I g. of commercial soap flakes were added: 0.06 g. of ammonium persulfate and 0.1 g. ofsodium bisulfit'e werethen added: and the suspension was warmed ona water bath at 40 C. until polymerization was complete (12-24 hours). The polymer was precipitated from the soapy emulsion by the addition of a small amount of acetic acid. The-resulting polymer had a. softening: point of 31090. and was soluble in dimethylformamide.

Example 6.-Interpolymer-oj styrene and. 3-methylenephthalide 5 g. of. styrene and 5 g. of 3-methylenephthalide were placed in a flask; which contained 0.02 g; of "benzoyl peroxide, and the air in the flask was replaced by gaseous nitrogen. The fiask was. then heatedatlOOf C. for 48-hours on awater bath. The clear, hard mass, had a softening point of 252 C. and contained 76 percent by weight :of" 3-methylenephthalide.

The amount of S methylenephthalide in the polymer can becontrolledby: adding the 3-methylenephthalide to the reaction mixturedurin the course of the polymerization at a. rate approximating the rate it is used up. This might be desirable where a polymer having asoftening point sufiiciently low-for moldingpurposes-is de sired. The presence of large amounts of 3- methylenephthalide in the reaction mixture at any one time tends to produce a polymer of an unusually high melting point.

Example 7.-Interpolymer of acrylom'trile and S-methylenephthalide 8 g. of 3-methylenephth-alide and 2 g. of aerylonitrile weresuspendedin 100cc. ofacetic acidto which.0.1g. of acetylperoxide has been-added. The reactionmixture was then heated on a-water bath'f0r24; hours at 60 C. The white polymer which was thus obtained had amelting pointof 295 C. and was soluble in N,'N-.-dimethylacet amide.

lnterpolymers of- 3-methylenephthalide and acrylonit-rile containing about '70 percent by weight of acrylonitrile areuseful in thepreparation of synthetic; fibers. The fibers can readily. be prepared by dissolving the interpolymerv indimethylformamide or N,N-dimethylac etamide and forcing the solution under pressure through a spinneret into a. coagulating 'bath. The fibers can be stretched 200-800 percent to increase their strength.

Example 8.-Interpolymer of acrylonitrile and 3-methyZenephthaZide-Emulsion method 5 g. of acrylonitrile, 5 g. of 3-methylenephthalide, 1 cc. of 10 percent hydrogen peroxide, 1 cc. of fiN-sulfuric acid and. 0.2 g. of. FeISO4.7H2O were added to cc. of distilled water containing 85 1. g. oi. commercial soap; flakes.v The mixturewas shaken. and the resultin emulsion allowed. to stand; at room; temperature. The. polymerization began almost at once and was complete within. 3 to 4 hours. Acetic; acid was. then added to. break the emulsion, and the precipitatedp lymer wasfilteredofi, and. washed free ofacidand ferric ions with distilled water.

Example 9-.Interpolymer of. 3-methylenephtluzlzclr:v and methyla-methacrylate 9 g. of 3-methylenephthalide 1. g,v of methyla-methacrylate, and 0.2. g. of. benzoyl. peroxide were, dissolved in 25 cc. of acetonitrile. The 80- lution was then heated on a, water bath at. 7.0?

C. for labours- The; precipitated white. polymer was obtained in. almost theoretical; yield.

Example 10.Interpolymer of3'-methylenephthalz'de and 2,5-dz'chl0rostyrene Example 11 .-Interpolymerof Il -methylenephthalid'e and oinylidene chloride 5' g. of3-methylenephthalide, 5 g. of vinylidene chloride, 2 g. of commercial soap flakes; 0.1 g: of ammonium persulfate and 0.2 g. of ammonium bisulfite were added to cc. of distilled water in a pressure bottle after heating the closed bottle for 20 hours at 40 (3., acetic acid was added, and the precipitated polymer was filtered, Washed and then dried. The polymer had a-softening point. above C.

When a molecularly equivalent amount of, vinyl chloride replaces the vinylidene chloride; in the above example,. a. clear, hard polymer, having a high softening point can be obtained.

Byv substituting molecularly-equivalent amounts of other polymerizable compounds for those illustrated in the examples, other interpolymers exhibiting valuable molding, fiberand. film? forming properties can be obtained: Many of. the polymers of our invention, e. ginterpolymers. of styrene and 3-methylenephthalid'e,-. are useful in. the preparation of electrical insulating materials. The properties of the polymers, can be varied. during or after, polymerizatiomby inxcorporating therein certain plasticizing agents; e. g. di-n-butyl phthalate; camphor, di;-n.-butyl'j sebacate, di-p-ethoxyethyl succinate, tri'acetin; etc. Fillers, coloring matter, etc. canalso beincorporated in the polymers. Adhesivematerials can be prepared by interrupting the; polymerization before the polymer has set to a hard mass and while the polymer is still in a viscous or gummy state.

What. we claim as our invention and; desire secured by Letters Patent of theUnitedstat'esis:

1. A homopolymer of -methylenephthalide having a molecular weight of at least 10,000, said homopolymer being solublein N,N-dimethylform'- amide.

2. A homopolymer of- 3-methylenephthalide having a molecular weight of at least 10,000-and amelting point of at least 300C said'homopoly mer being soluble in N,N-dimethylformamidei 3. A homopolymer of 3.-methylenephthalide having a molecular weight of from 101100 to 9 250,000, said homopolymer being soluble in N,N- dimethylformamide.

4. A new composition of matter comprising a homopolymer of 3-methylenephthalide having a molecular weight of at least 10,000 and an amide 5 selected from the group consisting of N,N-dimethylformamide and N,N-dimethylacetamide.

5. A new composition of matter comprising a solution of a homopolymer of 3-methylenephthalide having a molecular weight of at least 10,000 10 in N,N-dimethylformamide.

10 6. A new composition of matter comprising a solution of a homopolymer of 3-methy1enepthalide having a molecular weight of at least 10,000 in N,N-dimethylacetamide.

HARRY W. COOVER, JR. JOSEPH B. DICKEY. NEWTON H. S-HEARER.

No references cited. 

4. A NEW COMPOSITION OF MATTER COMPRISING A HOMOPOLYMER OF 3-METHYLENEPHTHALIDE HAVING A MOLECULAR WEIGHT OF AT LEAST 10,000 AND AN AMIDE SELECTED FROM THE GROUP CONSISTING OF N,N-DIMETHYLFORMAMIDE AND N,N-DIMETHYLACETAMIDE. 